Saturday, August 15, 2015

Hammers, chisels, birds and beards

Imagining the history of the earth is an old pursuit. From fascinating tales of floods and elaborate fantasies of rat-designed Norwegian coastlines, ideas on landform origins have been built up by piecing jig-saws of evidence from fragments of coastline, fossils, magnetometry, isotope markers and a growing range of tools. The early geologists had far fewer tools but that was probably made up for by a great deal more excitement. Imagine calculating the rates of deposition of sediment and calculating the age of cliffs to find that it did not meet Biblical teachings. Early geologists had to tread with caution, but it was probably much easier if you were far away in places like India. The profession of geology in India can be traced to the period when travelling from Europe to the colonies in India became faster with steamships. Steamships evolved from using auxiliary paddles to propellers and screws. Steamships required coal and it was not always easy to store enough for a journey or even to stash along the route. The geology of coal was essentially a study of old forests, paleontology, and the people involved in its quest in India saw the land through a scientific lens (and toolkit) that differed from that of the physician naturalist (and of course that of the parson naturalist). The geologists tended to have a much keener sense of spatial patterns, associations with climate, patterns of dispersal and how land barriers may have worked to separate populations and create species.We have already seen how Professor Robert Jameson's geology classes, attended by the likes of T.C. Jerdon and Charles Darwin had an enormous influence on them despite Darwin's claim that "the sole effect they [Jameson’s lectures] produced on me was the determination never as long as I lived to read a book on Geology, or in any way to study the science"! It is unsurprising that geologists in this period were fairly well-rounded naturalists.

There is an interesting old picture of the members of the Geological Survey of India in 1870. All of them are bearded, several from Ireland, and a couple of Europeans (a Moravian and a German) influenced by studies in Austria. Of this bunch, the man at the extreme left - Ferdinand Stoliczka, would contribute greatly to ornithology before dying young of altitude sickness. Standing fourth and fifth from left are F.R. Mallet and Valentine Ball who were also keen ornithologists. Ball was also into ethnology and when the first railway lines were being laid, he would advice the government on the best paths in central India to connect the coal fields of the Chota Nagpur Plateau with the port of Bombay. Both Ball and Mallet were Hume collaborators. Ball even joined Hume on the Andaman expedition and his name lives on in Otus balli. We get some idea of their zeal for collection from the writings of another Czech/Austrian who came replace the paleontological position held by Stoliczka. Otokar Feistmantel notes how they would travel with a large retinue of servants, three elephants and lavish field tenting arrangements. He pointed out that he was free to use the gun as he liked - somethingthat only the royalty could do back in Europe. Feistmantel's also notes on how European life in Calcutta revolved around the beach also make for interesting reading in modern times. The grand work on the Fauna of British India series was put under the editorship of a geologist W. T. Blanfordwhile his brother H. F. Blanford went on to lead the creation of the Indian Meteorological Department, the order for its establishment being signed by Hume himself (although Blanford gives more credit to Richard Strachey, one of Hume's "opponents" in the Agriculture Department).

More recent ornitho-geologists like Jürgen Haffer took to geology as a secure career with the added prospect of travel. He however worked extensively on bird speciation in South America. He also wrote a biographical note on his mentor Ernst Mayr and bits on the history of European ornithology.And from there we get to even more modern geologists who do not even have to travel to propose very interesting hypotheses in ornithology. In a series of articles by a team of geologists the idea is proposed that grain size and soil properties create a somewhat narrow window of opportunity for large hole nesters and that the mechanical properties needed to support such burrows without collapsing are met by a specific soil type:- loess. The authors examine the breeding distributions of birds with loess deposits and find a substantial overlap. This naturally makes everyone worry that confirmation bias involved but the idea is clearly a very testable hypotheses and probably needs a lot more reading that it is getting especially within the ornithological community.With modern academic specialization, it seems that geology and ornithology are never packed into the same person nor are persons from the fields teaming up. So it comes as a nice surprise to see some bold and fresh thinking in a recent series on the distributions of large hole burrowing bee-eaters. Looking at the citations of these series, it is a bit depressing to see that ornithologists do not seem to think too highly of the work. Heneberg points out that the original work does not take biological variables into account which is clearly why we need more interdisciplinary (if not antidisciplinary ie against subject boundaries) attitudes. As someone who was at least marginally trained in soil science, I found it rather interesting and was wondering how interesting it would be to conduct such studies in India on soil types and hole nesting birds. I would certainly encourage anyone who is not in the academic rat-race to take an interest in such ideas and appreciate the beauty of interdisciplinary scientific hypotheses, even if it eventually turns out to be more complex.

The overlap of loess deposits and the European bee-eater breeding zones from Smalley et al. (2013).
All rights belong to the author and publisher and are used here under a fair use rationale.

Thinking about this locally and from a precautionary perspective, it might be worth examining the soil type at Naguvanahalli, Srirangapatna where the blue-tailed bee-eaters nest. If the soil type is indeed special and restricted in its distribution, it might call for more concerted conservation action.

PS: I found this video above and it shows blue-tailed bee-eaters burrowing into near-horizontal ground, I am not sure this is actually documented anywhere! Ali & Ripley in their Handbook. Volume 4:106 mention this nesting habit for Merops superciliosus persicus.

Another bit of footage from Azerbaijan, thanks to Tatiana Petrova.References

Do also look at the blog of the author Ian Smalley - http://loessground.blogspot.in/NoteIt has taken a while to write out this piece, mostly because it has taken quite a while to research and write Feistmantel's biography on Wikipedia. Anyone having issues accessing these papers are welcome to write for a copy.

1 comment:

My 8 year old son interested in the Dinosaurs also got interested in the Geological time scale. He also tells me that birds evolved out of raptor-like Theropods. Competence in Geology is a great advantage in becoming a well-rounded naturalist. The link between soil types and hole nesting birds is certainly interesting.